Backbone Route filters v0.1.2

Backbone Route filters allows you to have a pre-condition for the router using before filters and some "after" routing calls using after filters. Before filters could prevent router from calling action in case any of them returns false.

Note that after filters are executed only of before filters are passed and original route executed

Filters are inherited by extending parent's filters with child's. Child's filter have higher priority, so having same pattern in child filters will override parent's behaviour.

Filters are also supporting async mode via calling next callback when filter finished. This callback should be explicitly passed as third argument to the filter function. See checkAuthorization in example below.

Installation

Using Bower bower install backbone-route-filter or just copy backbone-route-filter.js

Usage

var Router = Backbone.Router.extend({
  routes: {
    'users': 'usersList',
    'users/:id': 'userShow',
    'account/sign-in': 'signIn'
  },

  before: {
    // Using instance methods
    'users(:/id)': 'checkAuthorization',

    // Using inline filter definition and `return false` if don't want route to be executed
    '*any': function(fragment, args) {
      var hasAccess = CurrentUser.hasAccessTo(fragment, args);
      
      if (!hasAccess) {
        Backbone.navigate('/', true);
      }
      
      return hasAccess;
    }
  },

  after: {
    // Google analytics tracking
    // After filter will be triggered only if all before filters passed and action was triggered,
    // so you'll only track pages that was displayed to user
    '*any': function(fragment) {
      goog._trackPageview(fragment);
    }
  },

  checkAuthorization: function(fragment, args, next) {
    if (this._isSignedIn) {
      // If signed in - just proceed
      next();
    } else {
      // Requesting server to check if user is authorised
      var that = this;

      $.ajax({
        url: '/auth',
        success: function() {
          that._isSignedIn = true;
          next();
        },

        error: function() {
          Backbone.navigate('login', true);
        }
      });
    }
  }
});

Running tests

You can use karma runner via

npm install && grunt test

or directly hit html files spec/backbone-qunit.html and spec/jasmine.html to run Backbone's standard suite and Backbone route filter specs